The H II regions LMC N191 and SMC N77 are among the outermost massivestar-forming regions in the Magellanic Clouds. So far, few works have dealtwith these objects despite their interesting characteristics. We aim atstudying various physical properties of these objects regarding theirmorphology (in the optical and Spitzer IRAC wavelengths), ionized gas emission,nebular chemical abundances, exciting sources, stellar content, age, presenceor absence of young stellar objects, etc. This study is based mainly on opticalESO NTT observations, both imaging and spectroscopy, coupled with other archivedata, notably Spitzer images (IRAC 3.6, 4.5, 5.8, and 8.0 microns) and 2MASSobservations. We show the presence of two compact H II regions, alow-excitation blob (LEB) named LMC N191A and a high-excitation blob (HEB)named SMC N77A, and study their properties and those of their exciting massivestars as far as spectral type and mass are concerned. We also analyze theenvironmental stellar populations and determine their evolutionary stages.Based on Spitzer IRAC data, we characterize the YSO candidates detected in thedirection of these regions. Massive star formation is going on in these youngregions with protostars of mass about 10 and 20 M_sun in the process offormation.
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